fix(tools): exclude nested skill docs from strategy-3 flat search

[cjakma]

What changed and why

skill_view strategy-3 uses rglob(f"{name}.md") to find legacy flat skill docs. This was also picking up reference/template .md files that live inside another skill's directory (e.g. skills/foundations/runtime/references/explore-codebase.md) and returning them as match candidates for an unrelated skill name.

Added an ancestor-walk: if any directory between the found file and the search root contains a SKILL.md, the file belongs to that enclosing skill and is excluded from strategy-3 results.

How to test

# Create a reference file inside an existing skill that happens to share a name:
mkdir -p ~/.hermes/skills/some-skill/references/
echo "# doc" > ~/.hermes/skills/some-skill/references/other-skill.md
hermes -q "view skill other-skill"
# Should NOT return the reference file from inside some-skill/

Platforms tested

• Linux (Ubuntu 22.04)

Changes

• tools/skills_tool.py: strategy-3 loop now skips files whose ancestor chain contains a SKILL.md

[teknium1]

Thanks for the focused fix. Current main already provides this behavior.

• tools/skills_tool.py:1172-1180 excludes support documents from strategy-3 legacy-flat discovery via _is_skill_support_path.
• tests/tools/test_skills_tool.py:1228-1261 covers a nested references/styles/sketch.md and verifies skill_view("sketch") resolves the real skill instead.
• This supersedes the behavior proposed by this PR; the current implementation is present in commit d682f320b35a13084371a541a835e1d988c982b8.

Automated hermes-sweeper review.